Data communication that mainly uses an electrical wiring is currently being carried out in an electronic device including an electronic device (portable device) that can be carried such as a portable telephone. However, in recent years, development of data communication, that is, an optical communication network that employs an optical wiring that can be handled substantially similar to the electrical wiring is being advanced to more suitably implement data communication in such electronic devices.
The optical communication network is recently widely applied to an optical communication, optical network, optical interconnection, and the like as a data communication means enabling large capacity data communication at high speed. In such optical communication network, a plurality of electronic components configuring the electronic device is connected by a light transmission module (optical wiring), and data communication is carried out among the plurality of electronic components by transmitting signals of 1 GHz through the light transmission module. The signals for performing data communication are binary signals including a signal of “1” (signal of high level) and a signal of “0” (signal of low level).
The optical communication network has the following advantages. The first advantage is that optical characteristics and noise resistance property do not need to be taken into consideration when designing the electronic device. The second advantage is that the electronic device having strong mechanical characteristics can be realized at the coupling part or the like with the light guide configuring the light transmission module. The third advantage is that the plurality of electronic components can be electrically connected (connector connection), and miniaturization and lower height of the electronic device can be realized. Stating such advantages in one sentence, the optical communication network has advantages in that large capacity data communication can be easily realized and the degree of freedom in designing the electronic device for performing the large capacity data communication can be enhanced.
In the above-described optical communication network, the data communication is carried out according to the following procedure using the light transmission module.
The signal for performing data communication output from the electronic component on the transmission side is input to the light transmission device of the light transmission module as an electric signal. The light transmission device converts the signal from the electronic component on the transmission side from an electric signal to an optical signal, and transmits the same to the light reception device of the light transmission module through a light transmission medium (e.g., light guide). The light reception device converts the signal received from the light transmission device from the optical signal to the electric signal, and provides the same to the electronic component on the reception side.
As apparent from the procedure of the data communication described above, the step of data communication includes a step of processing the electric signal and a step of processing the optical signal in the optical communication network. A means for processing the electric signal and a means for processing the optical signal are suitably integrated in order to easily handle the optical communication network and promote miniaturization of the electronic device for performing data communication with the optical communication network.    Patent Document 1: Japanese Laid-Open Patent Publication No. 2006-229981 (date of publication: Aug. 31, 2006)    Non-patent Document 1: Hiroto Watanabe, Masayuki Kuwabara, Seiji Sakaguchi, Asaya Yokoyama, Haruo Miyazawa, Nobuyuki Sadakata: “One review of high frequency characteristics of FPC”, Fujikura Technical Review, No. 110, P. 19-22, April, 2006.